1. Field of the Invention
The present invention relates to a cable tension device and, more particularly, to a cable tension device for tightening a cable to bind a cargo.
2. Description of the Related Art
A conventional cable tension device comprises a fixing seat, a rotation shaft rotatably mounted on the fixing seat to wind and unwind a cable, a ratchet unit secured on the rotation shaft to rotate the rotation shaft, a movable seat rotatably mounted on the rotation shaft, an locking plate mounted on the fixing seat and detachably engaged with the ratchet unit to allow the ratchet unit to rotate forward in one direction only, an elastic engaging board mounted on the movable seat and detachably engaged with the ratchet unit to drive the ratchet unit to rotate forward in the one direction only.
In operation, when the movable seat is rotatable relative to the fixing seat forward, the engaging board is rotatable with the movable seat to drive the ratchet unit to rotate forward to rotate the rotation shaft forward so as to wind the cable. At this time, the locking plate is engaged with the ratchet unit to prevent the ratchet unit from being rotated backward. On the contrary, when the movable seat is rotatable relative to the fixing seat backward, the engaging board is rotatable with the movable seat to pass through the ratchet unit without interfering with operation of the ratchet unit. Thus, the movable seat is rotatable relative to the fixing seat forward successively to rotate the rotation shaft forward to wind and tighten the cable successively so as to bind a cargo.
However, the user easily applies an excessive force on the movable seat to tighten the cable too excessively by successive rotation of the movable seat, so that the cargo is easily worn or broken due to the excessive force applied by the cable.